i am a new member and a new owner of a Black BMW 325es it is a 1986 i am just wondering what i could possibly do to make it quciker i am shooting for 13second or 12 second quarter miles please pm me with and ideas. i have talked to a few people here in town and they say i should do a 325i head swap and turbo it with 10 psi but i have also thought about just completely swapping the engine for a 325 and i am wondering if anyone has a wiring diagram for either the head swap or engine swap please pm me with details thanks!:

Wow. An efficient 13-second quarter probably needs an M50.
Swapping another M20 and boosting it would work, but there's just so much more potential in a newer engine, especially for extreme goals like those. The S/M50/2 swaps are well documented all over the place, as is the Eta to turbo-i conversion.

But. For general romping about, a Conforti chip and a solid suspension will wake that car right up. Good luck.